Accordingly, since quipped with advantages of convenience, extension, and high transmission speed in use for users, universal serial bus (USB) transmission interface is widely applied in various computer peripheral devices, information appliance products (IA) or 3C consuming electrical products. It is a transmission interface tool, which human beings cannot live in work and family without.
A prior art USB apparatus structure, as shown in FIG. 1 and FIG. 2, is a USB application apparatus 10 having a USB connector 11 (Series A Plug), such as storage memory devices, e.g. flash drive, MP3 walkman, or digital voice recorder. A front end thereof is mainly a USB connector 11. An exterior structure of the USB connector 11 is a metal covering shell 113 round covering a carrying board 111. A bottom surface of the carrying board 111 is clung to an interior lower surface of the covering shell 113. A top surface of the carrying board 111 is naturally formed a connecting sandwich 115 capable of connecting to another USB connecting bracket (Series A Receptacle) (71, as shown in FIG. 8) with an interior upper surface of the covering shell 113.
Further, a plurality of connecting terminators 13 can be fixed at the top surface of the carrying board 111 which are respectively a VCC power source line 131, a GND power source line 137, a D+ data transmission line 133, and a D− data transmission line 135 wherein the D+ data transmission line 133 and the D− data transmission line 135 can be proceeded in transmitting data, and the VCC power source line 131 and the GND power source line 137 can accept working current supplied by a USB host or a power supply.
Further, a USB application module 15 with a length L1 is connected to a back end of the USB connector 11. The USB application module 15 uses a covering shell 155 to clad a circuit board 157. A memory element 153 for storing data and a control circuit 151 are fixed on a surface of the circuit board 157. Two ends of the control circuit 151 can connect to the memory element 153 and the connecting terminators 13, respectively. Furthermore, a protection cap 17 is further set. The protection cap 17 covers the USB connector 11 by a way of covering to achieve an object of protecting the USB connector 11.
In the previous mentioned prior art USB application apparatus 10, the carrying board 111 is a filled resin material. The only function is carrying and fixing the USB connecting terminators 13. However, quite a bit volume of the USB connector 11 is occupied. And therefore, it is hard to reduce the volume or length of the USB application apparatus 10. Whether manufacturing cost or portable convenience of the USB application apparatus 10, quite a bit waste and inconvenience are caused.
Further, in the prior art USB connector 11, the top surface of the carrying board 111 only has only a VCC power source line 131, a GND power source line 137, a D+ transmission line 133, and a D− transmission line 135, the data transmission lines are obviously not enough. Therefore, the working efficiency thereof is also limited. It cannot totally meet the requirements of the efficiency of the information products nowadays.
Further, the protection cap 17 of the prior art USB application apparatus 10 is fixed at the exterior surface of the USB connector 11 by a way of covering. This fixing way can achieve an object of protecting the USB connector 11, but it also increase the whole volume of the USB application apparatus 10.
Further, The prior art USB connector 11 and the USB covering shell 155 are made of different materials. Therefore, in the manufacturing process, both are manufactured individually then adhered together. This way, the inconvenience in manufacturing is increased, and dangling will be existed between the USB connector 11 and the USB covering shell 155 if the adhesive effect is not good in an adhering process. For a long time, corruption of the connecting line inside of the USB application apparatus 10 will be caused.